TEXAS JOURNEYMAN PLUMBER EXAM – PRACTICE QUESTIONS AND CORRECT ANSWERS (VERIFIED ANSWERS) PLUS RATIONALES 2026
Q&A | INSTANT DOWNLOAD PDF.
*Core Domains*
* Plumbing Math
* Fuel Gas Systems and Pipe Sizing
* Water Supply and Distribution Systems
* Sanitary Drainage and Venting Systems
* International Plumbing Code (IPC)
* Uniform Plumbing Code (UPC) Amendments
* Occupational Safety (OSHA)
* Texas State Statutes and Rules
*Introduction*
*The purpose of this practice assessment is to provide a rigorous and comprehensive
evaluation for individuals preparing for the Texas Journeyman Plumber licensure.
This exam evaluates the fundamental skills and technical knowledge required to
safely install, maintain, and repair plumbing systems in compliance with state
mandates. The assessment is structured using a combination of multiple-choice
and scenario-based questions, designed to mirror the actual exam environment.
A heavy emphasis is placed on real-world application, critical decision-making,
and the mastery of both the International Plumbing Code and Texas-specific
amendments to ensure professional competence and public safety.*
SECTION ONE: QUESTIONS 1–100
1. What is the minimum lead-free requirement for pipes, pipe fittings, and plumbing fittings according to the Safe Drinking Water Act?
A. 0.5 percent
B. 0.1 percent
🟢 C. 0.25 percent
D. 8.0 percent
,🔴 RATIONALE: Under the Safe Drinking Water Act and the IPC, "lead-free" is defined as a weighted average of not more than 0.25 percent lead
when used with respect to the wetted surfaces of pipes, pipe fittings, and plumbing fittings.
2. A plumbing apprentice is installing a water heater in a garage. At what height must the ignition source be located above the floor level?
A. 12 inches
🟢 B. 18 inches
C. 24 inches
D. 6 inches
🔴 RATIONALE: To prevent the ignition of flammable vapors that may be present on the floor of a garage, the IPC and UPC require that ignition
sources be elevated at least 18 inches above the floor.
3. Which of the following is the minimum size for a building sewer?
A. 2 inches
B. 3 inches
🟢 C. 4 inches
D. 1.5 inches
🔴 RATIONALE: While code may allow for smaller sizes in specific low-load scenarios, the standard minimum size for a building sewer to ensure
proper flow and prevent blockage is 4 inches.
4. When testing a DWV system with air, what is the required pressure that must be maintained for at least 15 minutes?
🟢 A. 5 psi
B. 10 psi
C. 2 psi
D. 15 psi
🔴 RATIONALE: For an air test on a drainage, waste, and vent (DWV) system, the system must be able to hold 5 psi of air pressure for a minimum
of 15 minutes without showing any leaks.
5. A horizontal drainage pipe has a diameter of 3 inches. What is the minimum required slope per foot?
A. 1/16 inch
🟢 B. 1/8 inch
, C. 1/4 inch
D. 1/2 inch
🔴 RATIONALE: For pipes with a diameter of 3 to 6 inches, the minimum slope required is 1/8 inch per foot to maintain adequate scouring
velocity.
6. What is the primary purpose of a P-trap in a plumbing system?
A. To regulate water pressure
B. To filter out solid waste
🟢 C. To prevent sewer gases from entering the building
D. To increase the speed of drainage
🔴 RATIONALE: P-traps are designed to hold a water seal that acts as a barrier, preventing foul odors and dangerous sewer gases from escaping
the drainage system into the living space.
7. In a fuel gas system, what material is prohibited for use as a gas piping material?
A. Black steel
B. Copper (Type L)
C. Corrugated Stainless Steel Tubing (CSST)
🟢 D. Cast-iron
🔴 RATIONALE: Cast-iron pipe is not an approved material for fuel gas piping systems due to its brittleness and potential for leakage at joints
under gas pressure.
8. A 40-foot length of copper pipe expands when heated. If the temperature increases by 100 degrees Fahrenheit, approximately how much will
the pipe expand?
A. 0.25 inches
B. 0.52 inches
🟢 C. 0.77 inches
D. 1.10 inches
🔴 RATIONALE: Copper has a linear expansion coefficient that results in approximately 0.0000095 inches per inch per degree F. For 40 feet (480
inches) at 100 degrees, the expansion is roughly 0.4-0.8 inches depending on specific alloy; standard tables cite ~0.8 inches for 100-degree rise
per 100ft, but per 40ft it equates to roughly 0.77 inches.
9. What is the maximum distance a manual shutoff valve can be located from a gas appliance?
Q&A | INSTANT DOWNLOAD PDF.
*Core Domains*
* Plumbing Math
* Fuel Gas Systems and Pipe Sizing
* Water Supply and Distribution Systems
* Sanitary Drainage and Venting Systems
* International Plumbing Code (IPC)
* Uniform Plumbing Code (UPC) Amendments
* Occupational Safety (OSHA)
* Texas State Statutes and Rules
*Introduction*
*The purpose of this practice assessment is to provide a rigorous and comprehensive
evaluation for individuals preparing for the Texas Journeyman Plumber licensure.
This exam evaluates the fundamental skills and technical knowledge required to
safely install, maintain, and repair plumbing systems in compliance with state
mandates. The assessment is structured using a combination of multiple-choice
and scenario-based questions, designed to mirror the actual exam environment.
A heavy emphasis is placed on real-world application, critical decision-making,
and the mastery of both the International Plumbing Code and Texas-specific
amendments to ensure professional competence and public safety.*
SECTION ONE: QUESTIONS 1–100
1. What is the minimum lead-free requirement for pipes, pipe fittings, and plumbing fittings according to the Safe Drinking Water Act?
A. 0.5 percent
B. 0.1 percent
🟢 C. 0.25 percent
D. 8.0 percent
,🔴 RATIONALE: Under the Safe Drinking Water Act and the IPC, "lead-free" is defined as a weighted average of not more than 0.25 percent lead
when used with respect to the wetted surfaces of pipes, pipe fittings, and plumbing fittings.
2. A plumbing apprentice is installing a water heater in a garage. At what height must the ignition source be located above the floor level?
A. 12 inches
🟢 B. 18 inches
C. 24 inches
D. 6 inches
🔴 RATIONALE: To prevent the ignition of flammable vapors that may be present on the floor of a garage, the IPC and UPC require that ignition
sources be elevated at least 18 inches above the floor.
3. Which of the following is the minimum size for a building sewer?
A. 2 inches
B. 3 inches
🟢 C. 4 inches
D. 1.5 inches
🔴 RATIONALE: While code may allow for smaller sizes in specific low-load scenarios, the standard minimum size for a building sewer to ensure
proper flow and prevent blockage is 4 inches.
4. When testing a DWV system with air, what is the required pressure that must be maintained for at least 15 minutes?
🟢 A. 5 psi
B. 10 psi
C. 2 psi
D. 15 psi
🔴 RATIONALE: For an air test on a drainage, waste, and vent (DWV) system, the system must be able to hold 5 psi of air pressure for a minimum
of 15 minutes without showing any leaks.
5. A horizontal drainage pipe has a diameter of 3 inches. What is the minimum required slope per foot?
A. 1/16 inch
🟢 B. 1/8 inch
, C. 1/4 inch
D. 1/2 inch
🔴 RATIONALE: For pipes with a diameter of 3 to 6 inches, the minimum slope required is 1/8 inch per foot to maintain adequate scouring
velocity.
6. What is the primary purpose of a P-trap in a plumbing system?
A. To regulate water pressure
B. To filter out solid waste
🟢 C. To prevent sewer gases from entering the building
D. To increase the speed of drainage
🔴 RATIONALE: P-traps are designed to hold a water seal that acts as a barrier, preventing foul odors and dangerous sewer gases from escaping
the drainage system into the living space.
7. In a fuel gas system, what material is prohibited for use as a gas piping material?
A. Black steel
B. Copper (Type L)
C. Corrugated Stainless Steel Tubing (CSST)
🟢 D. Cast-iron
🔴 RATIONALE: Cast-iron pipe is not an approved material for fuel gas piping systems due to its brittleness and potential for leakage at joints
under gas pressure.
8. A 40-foot length of copper pipe expands when heated. If the temperature increases by 100 degrees Fahrenheit, approximately how much will
the pipe expand?
A. 0.25 inches
B. 0.52 inches
🟢 C. 0.77 inches
D. 1.10 inches
🔴 RATIONALE: Copper has a linear expansion coefficient that results in approximately 0.0000095 inches per inch per degree F. For 40 feet (480
inches) at 100 degrees, the expansion is roughly 0.4-0.8 inches depending on specific alloy; standard tables cite ~0.8 inches for 100-degree rise
per 100ft, but per 40ft it equates to roughly 0.77 inches.
9. What is the maximum distance a manual shutoff valve can be located from a gas appliance?
